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Organization and Basis of Presentation - Summary of Subsidiaries VIEs and VIEs' Subsidiaries (Details) | 12 Months Ended
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Dec. 31, 2019
Variable Interest Entity [Line Items] |
Place of establishment | E9
Sunlands HK |
Variable Interest Entity [Line Items] |
Date of establishment/ acquisition | Oct. 06, 2015
Place of establishment | K3
Percentage of direct or indirect economic ownership | 100.00%
Principal activities | Investment holding
Wuhan Zhibo |
Variable Interest Entity [Line Items] |
Date of establishment/ acquisition | Aug. 02, 2017
Place of establishment | F4
Percentage of direct or indirect economic ownership | 100.00%
Principal activities | Provision of technical consultation and services
Tianjin Sunlands |
Variable Interest Entity [Line Items] |
Date of establishment/ acquisition | Jul. 31, 2017
Place of establishment | F4
Percentage of direct or indirect economic ownership | 100.00%
Principal activities | Provision of technical consultation and services
Wuhan Shangde Online Education Technology Co., Ltd. |
Variable Interest Entity [Line Items] |
Date of establishment/ acquisition | Jun. 25, 2019
Place of establishment | F4
Percentage of direct or indirect economic ownership | 100.00%
Principal activities | Provision of education services
Chengdu Xinketang Cultural Communication Co., Ltd. |
Variable Interest Entity [Line Items] |
Date of establishment/ acquisition | Nov. 04, 2019
Place of establishment | F4
Percentage of direct or indirect economic ownership | 100.00%
Principal activities | Sales of educational materials and books
Beijing Sunlands |
Variable Interest Entity [Line Items] |
Date of establishment/ acquisition | Sep. 27, 2013
Place of establishment | F4
Principal activities | Investment holding and provision of education services
Tianjin Shangde |
Variable Interest Entity [Line Items] |
Date of establishment/ acquisition | Mar. 21, 2018
Place of establishment | F4
Principal activities | Provision of education services
Beijing Shangzhi Jiaye Education Technology Co., Ltd |
Variable Interest Entity [Line Items] |
Date of establishment/ acquisition | Mar. 13, 2012
Place of establishment | F4
Percentage of direct or indirect economic ownership | 100.00%
Principal activities | Provision of education services
Beijing Shangren Chongye Education Technology Co., Ltd. |
Variable Interest Entity [Line Items] |
Date of establishment/ acquisition | Sep. 27, 2013
Place of establishment | F4
Percentage of direct or indirect economic ownership | 100.00%
Principal activities | Provision of education services
Guangdong Shangde Online Education Technology Co., Ltd. |
Variable Interest Entity [Line Items] |
Date of establishment/ acquisition | Oct. 15, 2013
Place of establishment | F4
Percentage of direct or indirect economic ownership | 100.00%
Principal activities | Provision of education services
Guangzhou Youhe Self-study Training School |
Variable Interest Entity [Line Items] |
Date of establishment/ acquisition | May 19, 2015
Place of establishment | F4
Percentage of direct or indirect economic ownership | 100.00%
Principal activities | Provision of education services
Beijing Heikuaima Education Technology Co., Ltd. |
Variable Interest Entity [Line Items] |
Date of establishment/ acquisition | Mar. 03, 2016
Place of establishment | F4
Percentage of direct or indirect economic ownership | 100.00%
Principal activities | Provision of education services
Shanghai Shangchi Education Technology Co., Ltd. |
Variable Interest Entity [Line Items] |
Date of establishment/ acquisition | Dec. 22, 2016
Place of establishment | F4
Percentage of direct or indirect economic ownership | 90.00%
Principal activities | Provision of education services
Shanghai Shangchi Institute |
Variable Interest Entity [Line Items] |
Date of establishment/ acquisition | Sep. 01, 2017
Place of establishment | F4
Percentage of direct or indirect economic ownership | 100.00%
Principal activities | Provision of education services
Guangzhou Shangzhi Side Education Technology Co., Ltd. |
Variable Interest Entity [Line Items] |
Date of establishment/ acquisition | Sep. 28, 2017
Place of establishment | F4
Percentage of direct or indirect economic ownership | 100.00%
Principal activities | Provision of education services

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- Definition The parent entity's interest in net assets of the subsidiary, expressed as a percentage. + References No definition available. + Details
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- Definition Description of the transactions or business conducted by the Variable Interest Entity (VIE), including how the VIE is financed. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 50 -Paragraph 16 -Subparagraph (c,d) -URI http://asc.fasb.org/extlink&oid=118582676&loc=SL6228967-111685 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 50 -Paragraph 5A -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=118582676&loc=SL6759159-111685 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph b -URI http://asc.fasb.org/extlink&oid=118582676&loc=d3e5747-111685 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 50 -Paragraph 4 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=118582676&loc=d3e5728-111685 Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=118582676&loc=d3e5747-111685 + Details
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